生物技术通报 ›› 2020, Vol. 36 ›› Issue (5): 159-168.doi: 10.13560/j.cnki.biotech.bull.1985.2019-0718

• 研究报告 • 上一篇    下一篇

共表达HAC1和分子伴侣基因对甘露聚糖酶在毕赤酵母中表达的影响

闵琪1, 高子涵1, 姚银1, 张华山2, 熊海容1, 张莉1   

  1. 1.中南民族大学生命科学学院,武汉 430074;
    2.湖北工业大学发酵工程省部共建教育部重点实验室,武汉 430068
  • 收稿日期:2019-08-14 出版日期:2020-05-26 发布日期:2020-06-03
  • 作者简介:闵琪,男,硕士研究生,研究方向:微生物酶工程;E-mail:min51777@163.com
  • 基金资助:
    国家自然科学基金青年科学基金项目(31802096),湖北省技术创新专项重大项目(2018ABA093)

Effect of Co-expression of HAC1 and Molecular Chaperone Genes on the Expression of Mannanase in Pichia pastoris

MIN Qi1, GAO Zi-han1, YAO Yin1, ZHANG Hua-shan2, XIONG Hai-rong1, ZHANG Li1   

  1. 1. College of Life Sciences,South-Central University for Nationalities,Wuhan 430074;
    2. Key Laboratory of Fermentation Engineering,Ministry of Education,Hubei University of Technology,Wuhan 430068
  • Received:2019-08-14 Published:2020-05-26 Online:2020-06-03

摘要: 为了提高甘露聚糖酶ManA在毕赤酵母中分泌表达的酶活,选择毕赤酵母内质网未折叠蛋白反应(Unfolded protein response,UPR)激活调控因子HAC1与5种毕赤酵母蛋白折叠相关的分子伴侣ERO1、PDI、PDI1、CPR5、BiP,通过构建pPICZA-HAC1等6种胞内表达重组质粒,分别电转化至分泌表达ManA的毕赤酵母重组菌中胞内共表达,并分析其重组菌摇瓶发酵时ManA表达的影响。结果发现在摇瓶发酵水平,胞内共表达HAC1、ERO1、PDI的重组菌发酵上清液中的ManA酶活力分别提高了26%、15%、20%,其重组菌发酵上清液的酶活力分别达到1 014 U/mL、925 U/mL、965 U/mL。通过对各重组菌上清液酶活力、胞内滞留酶活力、上清液蛋白浓度数据进行分析,进一步选择将HAC1、ERO1、PDI进行两基因或三基因组合,并分别在分泌表达ManA的重组菌胞内共表达,但各共表达重组菌发酵上清液的酶活力都没有进一步的提升。单独共表达HAC1或者分子伴侣ERO1、PDI可以辅助ManA的正确折叠,提高其蛋白表达。

关键词: 甘露聚糖酶, 毕赤酵母, HAC1基因, 分子伴侣, 蛋白表达

Abstract: For the higher activity of expressed mannanase ManA in Pichia pastoris,the unfolded protein response(UPR)activation factor HAC1 and 5 reported endoplasmic reticulum protein folding related chaperones ERO1,PDI,PDI1,CPR5,and BiP in P. pastoris were constructed to have 6 intracellular-expressing recombinant plasmids,then each was electro-transformed into recombinant strain P. pastoris secreting ManA for intracellular co-expression respectively,and the influence of the recombinant strain on the expression of ManA during the shake-flask fermentation were analyzed. The results showed that the enzyme activity of ManA in the supernatant of the recombinant strain with co-expressing HAC1,ERO1 and PDI increased by 26%,15% and 20%,and the enzyme activity reached 1 014 U/mL,925 U/mL and 965 U/mL at the shake-flask fermentation. By analyzing the data of enzyme activity in supernatant,intracellular-retention enzyme activity,and protein concentration in supernatant as well as further selecting HAC1,ERO1,PDI to have 2 genes or 3 genes combinations,which then co-expressed in the recombinant strains secreting and expressing ManA,while the enzyme activity in the fermentation supernatants of each co-expressed recombinant strain was not further increased. Co-expression of HAC1 or molecular chaperone ERO1,and PDI separately enhanced the correct folding of ManA and thus increased the expression of the protein.

Key words: mannanase, Pichia pastoris, gene HAC1, molecular chaperones, protein expression